Enrichment and identification of cyclized hopanoids from Shengli lignite

Fourteen cyclized hopanoids, including hydrobenzohopanes, benzohopanes, and rearranged benzohopanes, were enriched from Shengli lignite via fractional extraction and preparative medium-pressure liquid chromatography. Their structures were tentatively identified by gas chromatography/mass spectrometry. Rearranged benzohopanes, which were unreported before, are probably produced from the corresponding benzohopanes via methyl rearrangement reaction.